Slotting cutter

ABSTRACT

A slotting cutter including a support disc rotatable in a predetermined direction on a central axis. The support disc is of a generally cylindrical shape having a first side and a second side, and an outer periphery. A plurality of pockets are staggered about the outer periphery of the support disc and includes a cutting insert secured in each pocket. Each cutting insert includes at least one cutting edge. The cutting insert extends laterally outwardly beyond the first side of the support disc and is spaced from the second side of the support disc such that the cutting edge of adjacent inserts are positioned to laterally overlap thereby providing an increased effective cutting path width.

FIELD OF THE INVENTION

The present invention relates to a slotting cutter. More particularly,the present invention relates to a slotting cutter including multipleopposing inserts capable of cutting to a flat bottom and also contourcutting the side and/or the bottom of a slot in a work piece in as manyas 5 axes.

BACKGROUND OF THE INVENTION

Slotting cutters are known for cutting keyways and the like and, also,for providing a work piece with slots of various width.

Slotting cutters of the nature referred to are somewhat similar tomilling cutters in that the cutter usually employs a disc-like memberhaving cutting inserts mounted in the periphery thereof. In a millingcutter, the cutting inserts are generally presented axially, whereas, ina slotting cutter, the cutting inserts protrude radially from thesupporting disc and are, thus, presented to the work piece in the radialdirection.

For a more detailed description of the operation of a slotting cutterreference is made to U.S. Pat. No. 3,940,835, incorporated herein byreference.

In order to form slots rapidly and efficiently, it is essential that thecutting inserts be solidly supported in the support disc and haveadequate clearance between the cutting edges of the inserts and thesupport disc as the material is removed from the work piece. With theinserts solidly supported and having sufficient clearance between thesupport disc and the cutting edges, the slotting cutter is able towithstand substantial loads and can cut extremely rapidly, freely andaccurately while maintaining the ability to easily discharge largevolumes of chips that may be generated during the cutting process.

With the foregoing in mind, a primary object of the present invention isthe provision of a slotting cutter of improved design.

Another object is the provision of a cutting insert for detachablymounting in the slotting cutter and especially adapted for usetherewith.

BRIEF SUMMARY OF THE INVENTION

Briefly, according to the present invention, there is provided aslotting cutter, including a support disc rotatable in a predetermineddirection on a central axis. The support disc is of a generallycylindrical shape having a first side and a second side, and an outerperiphery. A plurality of pockets are staggered about the outerperiphery of the support disc. A cutting insert is secured in eachpocket. Each cutting insert includes at least one cutting edge. Thecutting insert extends laterally outwardly beyond the first side of thesupport disc and is spaced from the second side of the support discwhereby the cutting edge of adjacent inserts are positioned to laterallyoverlap thereby providing an increased effective cutting path width.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as other features and advantages of the invention,will become apparent through consideration of the detailed descriptionin connection with the several drawings in which:

FIG. 1 is a perspective view of a slotting cutter according to thepresent invention;

FIG. 2 is a side view of the slotting cutter of FIG. 1;

FIG. 3 is an end view of the slotting cutter of FIG. 1;

FIG. 4 is an enlarged partial view of the slotting cutter of FIG. 3;

FIG. 5 is an enlarged partial side view of the slotting cutter of FIG.2; and

FIG. 6 is a perspective view of a cutting insert for use in the slottingcutter of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings wherein like reference characters representlike elements, there is shown a slotting cutter 10. The slotting cutter10 includes a support disc 12 that is rotatable in a predetermineddirection on a central axis perpendicular to the plane of the disc. Whenusing the slotting cutter at high speed, a balance screw may be used tomaintain the rotational balance of the support disc.

The support disc is of a generally cylindrical shape having an outerperiphery 14, a first side 50, and a second side 46. A central hubregion 16 extends through the first side 50 and second side 46 and isprovided with a bore 18 with a keyway 20 for receiving a drive key of asupport shaft. As well known in the art, rotative motion is imparted tothe slotting cutter 10 via the drive key which mates with drive keyway20.

In a preferred embodiment, the support disc 12 width may be about ½ to 3inches or more and the diameter may be about 7.8 inches or moredepending upon the desired application. Furthermore, the first andsecond side 50 and 46 of the support disc may be tapered to aid in chipexit and cutter clearance during 5-axis cutting.

Provided about the periphery of the support disc 12 are a plurality ofstaggered pockets 22 for receiving cutting inserts 24 including at leastone cutting edge. As shown in FIG. 5, the cutting inserts 24 are fixedin position at a positive angle θ₁ to cut the work piece W andefficiently remove the chips.

The cutting inserts 24 may be of a type well known in the art. Thecutting inserts 24 typically have a first face 26 and a second face 28which are generally parallel to and opposing each other. A first end 30and a second end 32 are between the first and second faces,respectively. A top end 34 and a bottom end 36 are between the first andsecond faces and intersect with first and second ends. The intersectionof top end 34 and first end 30 and bottom end 36 and second end 32 is inthe form a radiused corner 38. Each of the cutting inserts 24 isprovided with a cutting edge 40 at the intersection of the first face 26and top end 34 and the second face 28 and bottom end 36. Each insert 24,thus, has two cutting edges 40 and these cutting edges can beselectively presented to a workpiece by loosening an insert and indexingthe insert about an axial axis and then again clamping the insert in thepocket as further described herein. As well known in the art, thecutting inserts 24 may be formed of a hard wear resistant material suchas cemented carbide and the like.

The pockets 22 of the slotting cutter are substantially complementary inshape to the shape of the cutting inserts 24 to assist in accurateplacement of the cutting inserts and, optionally, to prevent the insertsfrom rotating in response to the forces applied to its cutting edgesduring a cutting operation. More particularly, the pockets 22 of theslotting cutter 10 are configured to provide increased lateral clearancebetween the cutting edges 40 and the ends 30 and 32 of the inserts 24and the support disc 12. The pockets 22 are positioned about thecircumference of the support disc 12 in an axially and radiallystaggered relationship to define left hand and right hand pockets.

It will be appreciated that most any suitable number of pockets 22 maybe formed in the support disc 12 depending upon the desired material ofthe work piece to be cut and the diameter of the support disc. Althoughmost any suitable number of pockets 22 may be employed, there must be aneven number of pockets to provide an equal number of cutting inserts forcutting the work piece. In a preferred embodiment, the slotting cutter10 includes eight pockets 22 equally spaced about the perimeter of thesupport disc 12.

As shown in FIG. 2, each pocket 22 opens radially outwardly as definedby a rear wall 42 and a bottom wall 44. The rear walls 42 of adjacentpockets 22 are positioned about the circumference of the support disc 12at an angle θ₂ of approximately 45 degrees thereby defining eight totalpockets in the support disc.

Referring to FIGS. 2 and 3, the rear walls 42 of the pockets 22 areformed within the perimeter of the support disc 12 and extend radiallydownwardly into the support disc and extend laterally from a first side50 of the support disc to a side support member 48 that is offset orspaced from a second side 46 of the support disc. It will be appreciatedthat the side support member 48 is spaced from the second side 46 of thesupport disc 12 to provide clearance between the second side of thesupport disc and the cutting edge 40. Secured in position, every othercutting insert 24 extends laterally outwardly beyond the first side 50of the support disc 12 and is spaced from the second side 46 of thesupport disc thereby providing increased side clearance for chip removalduring the cutting process.

In a preferred embodiment, the inward side of the cutting edges 40 ofadjacent inserts 24 are positioned to laterally overlap therebyproviding an increased effective cutting path width. In addition, thecutting edges 40 of each insert are positioned within the pocket at thesame radial distance from the central axis C. Accordingly, there is nooverlap line presented by the cutting edges 40 of the inserts 24 alongthe periphery 14 of the slotting cutter 10 as the inserts cut a workpiece.

The bottom wall 44 of each pocket 22 is substantially perpendicular to aradial line 52 of the support disc 12. The bottom wall 44 extendsoutwardly from the rear wall 42 toward the rear of the next precedingpocket. The bottom wall 44 is connected to the next preceding pocketthrough a connecting section that may curve upwardly to the rear wall 42or that may extend linearly toward the rear of the next pocket. Forexample, in a preferred embodiment, the bottom wall 44 is spaced about 3inches along the radial line 28 of a 7.8 inch diameter support disc 12.

It will be appreciated that the rake angle of the cutting inserts 24 incombination with the offset side support member 48 of the pocket 22provides improved clearance and allows the cutter 10 to slot to a flatbottom and also contour cut the side and/or bottom of a slot in as manyas 5 axes in a suitable multi axis powered cutting tool. In addition, itwill also be appreciated that the bottom wall 44 extending outwardlyfrom the rear wall 42 allows for easy access to the insert 24 asnecessary for replacement.

The cutting inserts 24 may be fastened directly to the rear walls 42 ofthe pockets 22. A mounting screw 66 extends through a through an opening68 in the insert 24 and engages a threaded opening in the rear wall ofthe pocket (FIGS. 1-5). Alternatively, a clamping mechanism of a typeknown in the prior art may be used to secure the insert.

Having described presently preferred embodiments of the invention, theinvention may be otherwise embodied within the scope of the appendedclaims.

What is claimed is:
 1. A slotting cutter comprising: a support discrotatable in a predetermined direction about a central axis, the supportdisc of a generally cylindrical shape having a first side and a secondside, an outer periphery, and a central hub region extending through thefirst side and the second side having a bore, the first side and thesecond side of the support disc tapered inwardly from the outerperiphery to the central hub region; a plurality of pockets staggeredaround the outer periphery of the support disc, each pocket openingradially outwardly and defined by a rear wall and a bottom wall, therear wall formed within the outer periphery of the support disc andextending radially downwardly into the support disc, the bottom wallextending outwardly from the bottom of the rear wall toward the outerperiphery and toward the rear of the next preceding pocket and connectedto the next preceding pocket through a connecting section, a pluralityof side support members, each side support member extending radiallyoutwardly from the bottom wall to the outer periphery and laterallyalternating between a first position axially offset from the second sideand a second position axially offset from the first side, wherein eachside support member is tapered inwardly from the bottom wall to theouter periphery, wherein the rear wall alternates between a firstposition extending laterally from the first side to the side supportmember that is offset from the second side and a second positionextending laterally from the second side to the side support memberoffset from the first side; and a cutting insert secured in each pocketincluding at least one cutting edge, wherein the cutting insertsalternatingly extend from the side support member laterally outwardlybeyond the side of the support disc whereby the cutting edge of adjacentinserts are positioned to laterally overlap thereby providing anincreased effective cutting path width.
 2. The slotting cutter of claim1 wherein the cutting edge of every other insert is positioned within arespective one of the pockets at the same radial distance from thecentral axis of the support disc.
 3. The slotting cutter of claim 1wherein each cutting insert has a first face and a second face generallyparallel to and opposing one another, a first end and a second endpositioned between the first and second faces, respectively, a top endand a bottom end positioned between the first and second faces andintersecting with the first and second ends whereby the intersection ofthe top end and the first end and the bottom end and the second end isin the form of a radiused corner.
 4. The slotting cutter of claim 3wherein the at least one cutting edge is at the intersection of thefirst face and the top end.
 5. The slotting cutter of claim 3 whereinthe at least one cutting edge is at the intersection of the second faceand the bottom end.
 6. The slotting cutter of claim 3 wherein arespective one of the cutting inserts includes two cutting edges.
 7. Theslotting cutter of claim 6 wherein the cutting edges are at theintersection of the first face and the top end and at the intersectionof the second face and the bottom end.
 8. The slotting cutter of claim 1wherein a respective one of the cutting inserts is secured at a positiveangle.
 9. The slotting cutter of claim 1 wherein the bottom wall of eachpocket is formed within the outer periphery of the support disc.
 10. Theslotting cutter of claim 9 wherein the bottom wall of each pocket issubstantially perpendicular to a radial line of the support disc.
 11. Aslotting cutter comprising: a support disc rotatable in a predetermineddirection about a central axis, the support disc of a generallycylindrical shape having a first side and a second side, an outerperiphery, and a central hub region extending through the first side andthe second side having a bore, the first side and the second side of thesupport disc tapered inwardly from the outer periphery to the centralhub region; a plurality of pockets staggered around the outer peripheryof the support disc, each pocket opening radially outwardly and definedby a rear wall and a bottom wall, the rear wall formed within the outerperiphery of the support disc and extending radially downwardly into thesupport disc, the bottom wall extending outwardly from the bottom of therear wall toward the outer periphery and toward the rear of the nextpreceding pocket and connected to the next preceding pocket through aconnecting section, a plurality of side support members, each sidesupport member extending radially outwardly from the bottom wall to theouter periphery and laterally alternating between a first positionaxially offset from the second side and a second position axially offsetfrom the first side, wherein each side support member is taperedinwardly from the bottom wall to the outer periphery, wherein the rearwall alternates between a first position extending laterally from thefirst side to the side support member that is offset from the secondside and a second position extending laterally from the second side tothe side support member offset from the first side; and a cutting insertsecured in each pocket at a positive angle and including at least onecutting edge.
 12. The slotting cutter of claim 11 wherein the cuttingedge of each insert is positioned within a respective one of the pocketsat the same radial distance from the central axis of the support disc.13. The slotting cutter of claim 11 wherein a respective one of thecutting inserts has a first face and a second face generally parallel toand opposing one another, a first end and a second end positionedbetween the first and second faces, respectively, a top end and a bottomend positioned between the first and second faces and intersecting withthe first and second ends whereby the intersection of the top end andthe first end and the bottom end and the second end is in the form of aradiused corner.
 14. The slotting cutter of claim 13 wherein the atleast one cutting edge is at the intersection of the first face and thetop end.
 15. The slotting cutter of claim 13 wherein the at least onecutting edge is at the intersection of the second face and the bottomend.
 16. The slotting cutter of claim 13 wherein a respective one of thecutting inserts includes two cutting edges.
 17. The slotting cutter ofclaim 16 wherein the cutting edges are at the intersection of the firstface and the top end and at the intersection of the second face and thebottom end.
 18. The slotting cutter of claim 11 wherein the bottom wallof each pocket is formed within the outer periphery of the support disc.19. The slotting cutter of claim 15 wherein the bottom wall of eachpocket is substantially perpendicular to a radial line of the supportdisc.